Self-assembly of informational polymers such as nucleic acids (e.g., DNA and RNA) provides an effective approach for constructing sophisticated synthetic molecular nanostructures and devices (N. C. Seeman, Nature 421, 427 (2003)). The fundamental principle for designing self-assembled nucleic acid nanostructures is that sequence complementarity in nucleic acid strands is encoded such that, by pairing up complementary segments, the nucleic acid strands self-organize into a predefined nanostructure under appropriate physical conditions. From this basic principle (N. C. Seeman, J. Theor. Biol. 99, 237 (1982)), researchers have created diverse synthetic nucleic acid nanostructures (N. C. Seeman (2003); W. M. Shih, C. Lin, Curr. Opin. Struct. Biol. 20, 276 (2010)) such as lattices (E. Winfree, et al. Nature 394, 539 (1998); H. Yan, et al. Science 301, 1882 (2003); H. Yan, et al. Proc. Natl. Acad. of Sci. USA 100, 8103 (2003); D. Liu, et al. J. Am. Chem. Soc. 126, 2324 (2004); P. W. K. Rothemund, et al. PLoS Biology 2, 2041 (2004)), ribbons (S. H. Park, et al. Nano Lett. 5, 729 (2005); P. Yin, et al. Science 321, 824 (2008)), tubes (H. Yan Science (2003); P. Yin (2008)), finite two-dimensional (2D) and three dimensional (3D) objects with defined shapes (J. Chen, N. C. Seeman, Nature 350, 631 (1991); P. W. K. Rothemund, Nature 440, 297 (2006); Y. He, et al. Nature 452, 198 (2008); Y. Ke, et al. Nano. Lett. 9, 2445 (2009); S. M. Douglas, et al. Nature 459, 414 (2009); H. Dietz, et al. Science 325, 725 (2009); E. S. Andersen, et al. Nature 459, 73 (2009); T. Liedl, et al. Nature Nanotech. 5, 520 (2010); D. Han, et al. Science 332, 342 (2011)), and macroscopic crystals (J. P. Meng, et al. Nature 461, 74 (2009)). Many dynamic devices have been constructed in parallel (J. Bath, A. J. Turberfield Nature Nanotech. 2, 275 (2007)), including tweezers (B. Yurke, et al. Nature 406, 605 (2000)), switches (H. Yan, et al. Nature 415, 62 (2002)), walkers, (W. B. Sherman, N. C. Seeman, Nano Letters 4, 1203 (2004); P. Yin, et al. Nature 451, 318 (2008); T. Omabegho, et al. Science 324, 67 (2009)) and circuits (P. Yin (2008); G. Seelig, et al. Science 314, 1585 (2006); L. Qian, E. Winfree, Science 332, 1196 (2011)). Additionally, as DNA and RNA can be interfaced with other functional molecules in a technologically relevant way, synthetic nucleic acid nanostructures promise diverse applications. Researchers are using synthetic DNA/RNA nanostructures and devices to direct functional material arrangements (E A. Aldaye, et al. Science 321, 1795 (2008)), to develop bioimaging probes (H. M. T. Choi, et al. Nature Biotechnol. 28, 1208 (2010)), to organize and regulate molecular pathways in living cells (S. Venkataraman, et al. Proc. Natl Acad. Sci. USA 107, 16777 (2010); C. J. Delebecque, et al. Science 333, 470 (2011)), and to facilitate nuclear magnetic resonance (NMR) protein nanostructure determination (M. J. Berardi, et al. Nature 476, 109 (2011)).
An effective method for assembling megadalton nanoscale 2D (P. W. K. Rothemund (2006)) and 3D shapes (S. M. Douglas (2009); E. S. Andersen (2009); D. Han (2011)) is DNA origami, in which a long “scaffold” strand is folded to a predesigned shape via interactions with short “staple” strands. The requirement of a long scaffold-strand component (often viral genomic DNA) has limited the sequence and material choices of DNA origami nanostructures. Furthermore, each shape typically requires a new scaffold routing and therefore a completely different set of staple strands.